Is breather membrane waterproof?

Breather membranes, also known as breathable membranes or house wraps, are not typically designed to be fully waterproof. Their primary purpose is to provide a barrier against external moisture while allowing moisture vapor from inside the building to escape.

Breather membranes are commonly used in construction, particularly in walls and roofs, to improve the overall performance of the building envelope. They are made of microporous or semi-porous materials that allow water vapor to pass through while restricting the entry of liquid water. This helps to prevent condensation buildup within the walls and roofs, which can lead to issues like mold, rot, and deterioration of insulation.

While breather membranes can provide a degree of resistance against rainwater penetration, they are not intended to be relied upon as the primary waterproofing layer. Instead, they are used in conjunction with other building materials, such as waterproof membranes or cladding systems, to create a more robust and moisture-resistant structure.

It's important to note that the specific water resistance and vapor permeability properties of a breather membrane can vary depending on the manufacturer and product specifications. Therefore, it is recommended to consult the product documentation or contact the manufacturer to understand the exact characteristics and limitations of a particular breather membrane.